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Protein discovery promises to improve mapping of brain tumors

One of the problems with removing brain tumors is ensuring no cancerous tissue remains so they do not regrow. Now, a new study promises to reduce this problem – scientists have discovered a way to highlight a protein on brain scans so the edges of a tumor can be seen more clearly.
mri scanner
Researchers have found a promising way to show the edges of brain tumors in MRI scans more clearly.

The study, which offers scientists the most complete picture of brain tumors yet, is the work of a team from the University of Oxford in the UK, and was presented on Monday at the National Cancer Research Institute (NCRI) Cancer Conference 2015, in Liverpool, UK.

The edges of a tumor contain the most invasive cancercells. For surgery or radiation therapy to succeed, doctors need good maps that show not only where the tumor sits in the brain, but also where its edges are – a clear delineation between cancerous and healthy tissue.

This is important not only in order to remove all the cancerous tissue, but also because the most invasive cells are at the edge of a tumor, as one of the researchers, Cancer Research UK scientist Nicola Sibson, a professor in the Institute for Radiation Oncology at Oxford, explains:

“If we can’t map the edge of the tumor, surgery and radiotherapy often fail to remove aggressive tumor cells – and the brain tumor can grow back.

Currently, on magnetic resonance imaging (MRI) scans, you can see where the brain tumor is, but its edges are blurred. This is because the MRI spots leaky blood vessels inside the tumor. But on the edges of the tumor, the blood vessels are intact, so they do not show as clearly on the scans.

Highlights edges of both primary and secondary brain tumors

Now, for the first time, Prof. Sibson and her team have discovered a useful protein inside the blood vessels at the invasive edge of brain tumors.

In tests on rats, they showed it is possible to use the protein to define the edges of both primary and secondary tumors on MRI scans.

The protein – called VCAM-1 – is released as part of an inflammatory response caused by the brain tumor. The researchers developed a special dye that recognizes and sticks to the protein. The dye highlights the protein – and thus the edges of the tumor – on MRI scans.

An added advantage, note the researchers, is that the protein is on the inside of the vessels, so the dye can access it from the bloodstream.

Prof. Sibson concludes:

“This research shows that we can improve imaging of brain tumors, which could help both surgeons and radiotherapists with more effective treatment.”

Every year, around 256,000 people worldwide are diagnosed with cancer in the brain or another part of the central nervous system. In the UK, where the study was conducted, this figure is around 9,700, or 27 people a day.

“Brain cancers continue to have very poor survival rates,” says Harpal Kumar, chief executive of Cancer Research UK, which co-funded the study with the Medical Research Council. Kumar adds:

“The holy grail would be to be able to completely remove brain tumors with the help of this new imaging technique – reducing recurrence of the disease and saving more lives.”

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Sperm whales’ clicks suggest the animals have culture The whales appear to learn sounds to socialize, similar to the way humans learn language

sperm whale

Sperm whales love to chitchat. They talk to each other in clicks. Now, scientists say, those clicks hold hints that the whales have culture.

Culture is a way of life passed on from generation to generation through learning. “There’s a lot of debate if culture is exclusive to humans or if you can find it in animals, too,” says Maurício Cantor. He is a biologist at Canada’s Dalhousie University in Halifax, Nova Scotia. Earlier research had suggested that dolphins, primates, birds and a few other wild animals have culture. Sperm whales should be added to that list, Cantor and his colleagues now argue in the September 8 Nature Communications.Sperm whales can make some of the deepest dives of all the animals in the sea. They can plunge up to 2,250 meters (7,380 feet) below the ocean’s surface. And they can stay underwater for nearly 90 minutes. When diving, the whales send out loud clicks and listen for the echoes that bounce back after the clicks hit something close by. This is calledecholocation. It’s the animal equivalent of sonar, and the whales use it to hunt — mainly for large squid. But when the whales are not hunting, they use those clicks to chat with each other.

Females and their calves do most of the talking. Tens of thousands of them hang out in the warm waters of the South Pacific Ocean. They usually swim in small units of 12 or so moms, grandmas, aunts and friends. These gals all work together to raise their pod’s babies.

These units are part of larger groups of 30 to 300 whales, which belong to even larger communities, called clans. Individuals in each clan talk to each other using distinct patterns of clicks. These varying patterns are similar to dialects in human speech. A dialect is a regional pattern in speech. People in Boston, Mass., and Dallas, Tex., both speak English, for example. Yet they may use words differently or give them a different pronunciation. Those differences reflect their regional dialects.

Cantor and his colleagues wanted to know how the whales got their distinct dialects. The researchers followed groups of whales around the Galápagos Islands, off South America. Along the way, they recorded the whales’ identities and behaviors. The scientists logged the whales’ sounds and tracked with which other groups these sperm whales interacted.

Back in their lab, the scientists loaded all of these data into a computer. Then they programmed it to test different ways the whale dialects could have developed over thousands of generations. Perhaps the dialects developed by chance. Or there might have been some innate bits of sound passed from mom to baby through DNA. The computer program ruled out both of those scenarios. Instead, the analysis showed that the whales had to have learned their distinct dialects from the other whales around them.Scientists refer to this as social learning.

“Social learning is the foundation of culture,” Cantor says. Because sperm whales learn their dialects from their extended family, there are cultural differences between clans. The clans actually exist because of those cultural differences, he says.

Luke Rendell is a biologist at the University of St. Andrews in Scotland. He was not involved in the study. He points out that the new finding is based on a computer model of how the sperm whale dialects came to be. A model, though, can only simulate the real world. It is not a direct observation of what actually occurred. “Like all models, it is wrong, but it is also useful,” Rendell says.

The model suggests whales have a bias for the sounds of their own clan members, which shapes their society, Rendell notes. This kind of conformity, or sticking with individuals who behave the same, is thought to underpin a lot of human culture. In non-humans, however, it is considered rare. Finding hints that it exists in sperm-whale clans “really starts to lift the lid on cultural processes in non-human societies,” he says.

Cantor notes that the scientists are not suggesting that the whales’ sounds or culture are as complex or diverse as human cultures are. But, he says, “Whale culture, like human culture, seems to be very important for the whales’ social structure.”

Power Words

(for more about Power Words, click here)

bias   The tendency to hold a particular perspective or preference that favors some thing, some group or some choice. Scientists often “blind” subjects to the details of a test so that their biases will not affect the result.

biology  The study of living things. The scientists who study them are known as biologists.

clan    A large family or group of families that have much in common, both genetically and culturally.

computer model A program that runs on a computer that creates a model, or simulation, of a real-world feature, phenomenon or event.

culture  (in social science) The sum total of typical behaviors and social practices of a related group of people (such as a tribe or nation). Their culture includes their beliefs, values, and the symbols that they accept and or use. It’s passed on from generation to generation through learning. Once thought to be exclusive to humans, scientists have recognized signs of culture in several other animal species, such as dolphins and primates.

dialect  A form of language or pattern of communication that is distinct to a specific place or a social group.

DNA  (short for deoxyribonucleic acid) A long, double-stranded and spiral-shaped molecule inside most living cells that carries genetic instructions. In all living things, from plants and animals to microbes, these instructions tell cells which molecules to make.

dolphins  A highly intelligent group of marine mammals that belong to the toothed-whale family. Members of this group include orcas (killer whales), pilot whales and bottlenose dolphins.

echolocation  (in animals) A behavior in which animals emit calls and then listen to the echoes that bounce back off of solid things in the environment. This behavior can be used to navigate and to find food or mates. It is the biological analog of the sonar used by submarines.

generation  A group of individuals born about the same time or that are regarded as a single group. Your parents belong to one generation of your family, for example, and your grandparents to another. Similarly, you and everyone within a few years of your age across the planet -are referred to as belonging to a particular generation of humans.

innate  Something such as a behavior, attitude or response that is natural, or inborn, and doesn’t have to be learned.

model A simulation of a real-world event (usually using a computer) that has been developed to predict one or more likely outcomes.

pod    (in zoology) The name given to a group of toothed whales that travel together, most of them throughout their life, as a group.

primate  The order of mammals that includes humans, apes, monkeys and related animals (such as tarsiers, the Daubentonia and other lemurs).

programming  (in computing) To use a computer language to write or revise a set of instructions that makes a computer do something. The set of instructions that does this is known as a computer program.

scenario   A possible (or likely) sequence of events and how they might play out.

simulate  (in computing) To try and imitate the conditions, functions or appearance of something. Computer programs that do this are referred to as simulations.

social learning  A type of learning in which individuals observe the behavior of others and modify their own behavior based on what they see.

social network  Communities of people (or animals) that are interrelated owing to the way they relate to each other.

sonar  A system for the detection of objects and for measuring the depth of water. It works by emitting sound pulses and measuring how long it takes the echoes to return.

sperm whale  A species of enormous whale with small eyes and a small jaw in a squarish head that takes up 40 percent of its body. Their bodies can span 13 to 18 meters (43 to 60 feet), with adult males being at the bigger end of that range. These are the deepest diving of marine mammals, reaching depths of 1,000 meters (3,280 feet) or more. They can stay below the water for up to an hour at a time in search of food, mostly giant squids.

zoology  The study of animals and their habitats. Scientists who undertake this work are known aszoologists.


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Scientists have developed an eye drop that can dissolve cataracts

Researchers in the US have developed a new drug that can be delivered directly into the eye via an eye dropper to shrink down and dissolve cataracts – the leading cause of blindness in humans.

While the effects have yet to be tested on humans, the team from the University of California, San Diego hopes to replicate the findings in clinical trials and offer an alternative to the only treatment that’s currently available to cataract patients – painful and often prohibitively expensive surgery.

Researchers in the US have developed a new drug that can be delivered directly into the eye via an eye dropper to shrink down and dissolve cataracts – the leading cause of blindness in humans.

While the effects have yet to be tested on humans, the team from the University of California, San Diego hopes to replicate the findings in clinical trials and offer an alternative to the only treatment that’s currently available to cataract patients – painful and often prohibitively expensive surgery.

Affecting tens of millions of people worldwide, cataracts cause the lens of the eye to become progressively cloudy, and when left untreated, can lead to total blindness. This occurs when the structure of the crystallin proteins that make up the lens in our eyes deteriorates, causing the damaged or disorganised proteins to clump and form a milky blue or brown layer. While cataracts cannot spread from one eye to the other, they can occur independently in both eyes.

Scientists aren’t entirely sure what cases cataracts, but most cases are related to age, with the US National Eye Institute reporting that by the age of 80, more than half of all Americans either have a cataract, or have had cataract surgery. While unpleasant, the surgical procedure to remove a cataract is very simple and safe, but many communities in developing countries and regional areas do not have access to the money or facilities to perform it, which means blindness is inevitable for the vast majority of patients.

According to the Fred Hollows Foundation, an estimated 32.4 million people around the world today are blind, and 90 percent of them live in developing countries. More than half of these cases were caused by cataracts, which means having an eye drop as an alternative to surgery would make an incredible difference.

The new drug is based on a naturally-occurring steroid called lanosterol. The idea to test the effectiveness of lanosterol on cataracts came to the researchers when they became aware of two children in China who had inherited a congenital form of cataract, which had never affected their parents. The researchers discovered that these siblings shared a mutation that stopped the production of lanosterol, which their parents lacked.

So if the parents were producing lanosterol and didn’t get cataracts, but their children weren’t producing lanosterol and did get cataracts, the researchers proposed that the steroid might halt the defective crystallin proteins from clumping together and forming cataracts in the non-congenital form of the disease.

They tested their lanosterol-based eye drops in three types of experiments. They worked with human lens in the lab and saw a decrease in cataract size. They then tested the effects on rabbits, and according to Hanae Armitage at Science Mag, after six days, all but two of their 13 patients had gone from having severe cataracts to mild cataracts or no cataracts at all. Finally, they tested the eye drops on dogs with naturally occurring cataracts. Just like the human lens in the lab and the rabbits, the dogs responded positively to the drug, with severe cataracts shrinking away to nothing, or almost nothing.

The results have been published in Nature.

“This is a really comprehensive and compelling paper – the strongest I’ve seen of its kind in a decade,” molecular biologist Jonathan King from the Massachusetts Institute of Technology (MIT) told Armitage. While not affiliated with this study, King has been involved in cataract research for the past 15 years. “They discovered the phenomena and then followed with all of the experiments that you should do – that’s as biologically relevant as you can get.”

The next step is for the researchers to figure out exactly how the lanosterol-based eye drops are eliciting this response from the cataract proteins, and to progress their research to human trials.


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One night of sleep loss can alter clock genes in your tissues

Reading a biological clock in the dark

Swedish researchers at Uppsala University and the Karolinska Institute have found that genes that control the biological clocks in cells throughout the body are altered after losing a single night of sleep, in a study that is to be published in the Journal of Clinical Endocrinology and Metabolism.

“Previous research has shown that our metabolism is negatively affected by sleep loss, and sleep loss has been linked to an increased risk of obesity and . Since ablation of in animals can cause these disease states, our current results indicate that changes of our clock genes may be linked to such negative effects caused by sleep loss”, says Jonathan Cedernaes, lead author on the study and a researcher at Uppsala University.

For the study the researchers studied 15 healthy normal-weight men who on two separate occasions came to the lab for almost 2-night long stays. During the second night the participants slept as usual (over 8 hours) in one of the two sessions, while they were kept awake in the other of these sessions, but in random order. To minimize the influence of various environmental factors, light conditions, food intake and activity levels in the lab were strictly controlled and the participants were bed-restricted when they were kept awake.

Following the second night on both occasions that the men were studied, small were taken from the superficial fat on the stomach, and from the muscle on the thigh – two kinds of tissues that are important for regulating metabolism and controlling . Blood samples were also taken before and after the participants had consumed a sugar solution to test their insulin sensitivity, a practice commonly done to exclude the presence of diabetes or a metabolic state called impaired , which can precede type-2 diabetes.

Molecular analyses of the collected tissue samples showed that the regulation and activity of clock genes was altered after one night of sleep loss. The activity of genes is regulated by a mechanism called epigenetics. This involves chemical alterations to the DNA molecule such as methyl groups – a process called methylation – which regulates how the genes are switched on or off. The researchers found that clock genes had increased numbers of such DNA marks after sleep loss. They also found that the expression of the genes, which is indicative of how much of the genes’ product is made, was altered.

“As far as we know, we are the first to directly show that epigenetic changes can occur after sleep loss in humans, but also in these important tissues”, says Dr. Cedernaes. “It was interesting that the methylation of these genes could be altered so quickly, and that it could occur for these metabolically important clock genes”, he continues.

The changes that the researchers observed were however different in the adipose tissue and the skeletal muscle. “This could suggest that these important molecular clocks are no longer synchronized between these two tissues”, Dr. Cedernaes says. “As such, ‘clock desynchrony’ between tissues has been linked to metabolic pathologies, this could suggest that these tissue-specific changes were linked to the impaired glucose tolerance that our participants demonstrated after the night that they had been kept awake”

The researchers do not at this stage know how persistent these changes are. “It could be that these changes are reset after one or several nights of good sleep. On the other hand, epigenetic marks are suggested to be able to function a sort of metabolic memory, and have been found to be altered in e.g. shift workers and people suffering from type 2 diabetes”, Dr. Cedernaes points out. “This could mean that at least some types of or extended wakefulness, as in shift work, could lead to changes in the genome of your tissues that can affect your metabolism for longer periods”, Dr. Cedernaes concludes.


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Phones With The Highest Radiation

cell-700x350

According to new research from the Weizmann Institute of Science in Israel, certain cellphones may be exposing us to harmful levels of electromagnetic radiation.

Published in the Biochemical Journal, the study found that a single us of a specific cellphones for just 15 minutes can trigger brain cell changes associated with cancerous cell division.


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Citizen Scientists Discover Yellow “Space Balls”

Citizen scientists scanning images from NASA’s Spitzer Space Telescope, an orbiting infra-red observatory, recently stumbled upon a new class of curiosities that had gone largely unrecognized before: yellow balls.

“The volunteers started chatting about the yellow balls they kept seeing in the images of our galaxy, and this brought the features to our attention,” said Grace Wolf-Chase of the Adler Planetarium in Chicago.

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A new ScienceCast video examines “yellow balls” and their role in star formation. Play it

The Milky Way Project is one of many “citizen scientist” projects making up the Zooniverse website, which relies on crowdsourcing to help process scientific data.  For years, volunteers have been scanning Spitzer’s images of star-forming regions—places where clouds of gas and dust are collapsing to form clusters of young stars.  Professional astronomers don’t fully understand the process of star formation; much of the underlying physics remains a mystery. Citizen scientists have been helping by looking for clues.

Before the yellow balls popped up, volunteers had already noticed green bubbles with red centers, populating a landscape of swirling gas and dust. These bubbles are the result of massive newborn stars blowing out cavities in their surroundings. When the volunteers started reporting that they were finding objects in the shape of yellow balls, the Spitzer researchers took note.

Auroras Underfoot (signup)

The rounded features captured by the telescope, of course, are not actually yellow, red, or green—they just appear that way in the infrared, color-assigned images that the telescope sends to Earth. The false colors provide a way to humans to talk about infrared wavelengths of light their eyes cannot actually see.

“With prompting by the volunteers, we analyzed the yellow balls and figured out that they are a new way to detect the early stages of massive star formation,” said Charles Kerton of Iowa State University, Ames. “The simple question of ‘Hmm, what’s that?’ led us to this discovery.”

A thorough analysis by the team led to the conclusion that the yellow balls precede the green bubbles, representing a phase of star formation that takes place before the bubbles form.

“Basically, if you wind the clock backwards from the bubbles, you get the yellow balls,” said Kerton.

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An artist’s concept shows how “yellow balls” fit into the process of star formation.

Researchers think the green bubble rims are made largely of organic molecules called polycyclic aromatic hydrocarbons (PAHs). PAHs are abundant in the dense molecular clouds where stars coalesce. Blasts of radiation and winds from newborn stars push these PAHs into a spherical shells that look like green bubbles in Spitzer’s images. The red cores of the green bubbles are made of warm dust that has not yet been pushed away from the windy stars.

How do the yellow balls fit in?

“The yellow balls are a missing link,” says Wolf-Chase. They represent a transition “between very young embryonic stars buried in dense, dusty clouds and slightly older, newborn stars blowing the bubbles.”

Essentially, the yellow balls mark places where the PAHs (green) and the dust (red) have not yet separated. The superposition of green and red makes yellow.

So far, the volunteers have identified more than 900 of these compact, yellow features.  The multitude gives researchers plenty of chances to test their hypotheses and learn more about the way stars form.

Meanwhile, citizen scientists continue to scan Spitzer’s images for new finds. Green bubbles.  Red cores.  Yellow balls.  What’s next?  You could be the one who makes the next big discovery.  To get involved, go to zooniverse.org and click on “The Milky Way Project.”


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Killer seals develop a taste for shark guts

THAT shark’s fate is sealed. A seal has been spotted turning ecological roles upside-down by killing and eating blue sharks. If this turnabout proves common, ecologists might need to reassess the role of seals in marine ecosystems.

Chris Fallows, a dive-boat operator in Cape Town, South Africa, was photographing 10 blue sharks underwater when a young male Cape fur seal arrived and chased and killed five of them, eating their intestines (African Journal of Marine Science, doi.org/268).

Ordinarily, seals and blue sharks, which are roughly the same size, both prey on much smaller fish, squid and other marine life. Several species of seal also feed on smaller sharks, and blue sharks have been seen pursuing – though not catching – fur seals.

Fallows’s observations are the first time anyone has seen seals preying on such large sharks, says Hugues Benoit of the Canadian Department of Fisheries and Oceans in Moncton, New Brunswick.

Seal attack <i>(Image: Chris Fallows)</i>

Benoit suspects this behaviour is more common than anyone realises. By chowing down on their competitors, seals could alter ocean food webs in unexpected ways, he says. If seals help hold down shark populations, for example, it could boost populations of smaller fish.

If so, fisheries biologists may need to take that into account in managing fish populations.